In addition to Christian’s and Marks’s comments;
# Connect a piece of fuel line to the carb inlet. With the carb in its upright position, blow into the fuel line. If you can blow air into the carb, turn the carb upside down and blow into again. This time you should not be able to blow into the carb. If the carb passes this test, the needle valve should not be the issue.
# If the test above fails, with the carb upright, rap on the side of the carb with the handle of a screw driver. This should dislodge the needle valve if it was stuck.
# There is an internal fuel filter in the carb. Try cleaning that.
# If you’ve done all of the above and still having issues, check your fuel pump. It may have assembled incorrectly or the fuel lines are attached wrong.